Method of printing cinematographic films



July 7, 1925.

W. B. WESCOTT IETHOD OF PRINTING CINEMATOGRAPHIC FILMS Filed Nov. 16, 1921 Patented July 7, 1925.

UNITE STATES P TENT OFFICE.

ILLIAM mam wnsco'rr, or wELLnsnnY, nnssacnosnrrs, ASSIGNOB, BY HEBNE nssremmnrs, 'ro TEOHNICOLOR morrox rrcrunn conroan'rron, or nosron,

nassacnusnrrs, a coaronnrron or mun.

METHOD OF PRINTING CINEMATOGRAIHIC FILMS. I

, Application filed November 18,1821. Serial No. 515,583.-

To all whom it may concern:

Be it known that I, WILLIAM Bbn'ron' Wnsoo'r'r, a citizen of the United States of America, and resident of Wellesley, in the 5 county of Norfolk and State of Massachusetts, have invented new and useful Improvements in .Methods of Printin Cinematographic Films, of which the 0 lowing is a spemficatmn.

This invention relates to. cinematography and more particularly to cinematogra hic printin of the .multip ex type, that is, o the type a apted to print a plurality of series of complemental ima es.

In theprojection o motion pictures is has been found desirable in changing from one making the change abruptly, gradually to merge the folscene. to another, instead 0 lowing scene into the preceding scene so that as one scene fades out the other scene ,is gradually substituted, this process being known as a dissolving rocess. In the production of -ordinary b ack and white pictures this dissolving phenomenon is usually efiected by varying the size of the diaphragm opening in the camera while ex-,

posing the negatives from which the positives exhibiting the dissolving phenomenon are produced. That is, while exposing the latter portion of one series of views the diaphragm is gradually closed and while exposing the first portion of the'succeeding series of views the diaphragm is radually opened. Then in printlng thB'POSItlVBS the two serieslof views are overlapped by printing thefirst portion of the second series over the latter ortion of the first series.

While this method is fairly satisfactory for black and white cinematography it involves a number of disadvantages whichI purpose to overcome. In the former process the rate of decrease and increase in the intensity in the latter and former portions of the overlapped series of views is finally determined in the camera so that, if incorrect, it cannot be corrected either in printing or projecting and all pictures produced from the ne atives will be defective. While a skilled p otographer can usually detetmine the proper time to begin to reduce the intensity of the first seriesfhe frequently makes mistakes, and unless highly skilled an operator is usually too much occupied with other matters properly to attend to the production of co .more series of complemental this detail. Moreover, it is frequently desirable to eliminate the last or the first portion of a series of views and in the old process this involves cutting away the diminuendo or crescendo portions of the film and sacrificing the dissolving phenomenon.

serious objection to the I However, a more described dissolving rocess is met with in or pictures by multiby films having two or images, as for example one series recording the red aspect of the object field and a corresponding or plex films, that is,

complemental series recordin the; n aspect of the object field. As lly eseribed 1n the atent to Daniel F. Comstock, No.

21,283,08 the contrast adients of the ima es in the respectlve comp emental series, which are produced by the components of light of images formed by the light having a steeper than the images formed by the green component, in the two-color process for example. If the two contrast gradients coincide at the normal degree of exposure they diverge as they extend downwardly from the point of intersection, and as the intensity of the images of the respective complemental-series are decreased their contrast gradients difier more and more. 'Moreover, in the ordinary panchromatic negative film employed in motion picture work, and particularly in the film used in color work, the emulsion is exceedingly sensitive and thestraight'portion of the contrast gradients are correspondingly short. Thus, if the complemental pictures of normal intensity have the proper red component of contrast gradient different dominant hues, are different, the

relative color values, in the old dissolvmg process where the dissolving effect is introduced in the original negatives by varying the diaphragm opening in the camera, the degree of exposure is varied either upwardly or downwardly along the contrast gradients; and, owin to the fact that the contrast gradients %or the respective complemental series of images, for example the red series and the green series, diverge and have onl short straight portions, the pictures of diminished intensity will not have proper relative color values, particularly in the region below the straight portionsof the contrast gradients. The result is that if the complemental pictures of normal intensity have the proper relative color values thediminuendo or crescendo pictures will not" have the proper relative color values but W111 be. too green in the shadows.

The principal object of the present invention is to overcome the above and other difiiculties and to obtaina more convenient and adaptable method and means for efl'ectlng the dissolving phenomenon elther in black and white or color cinematography. To thls end the invention, in its preferred-form 1nvolves no variation of the intensity of the end portions of the original negatlve film as in the old process, but on the contrary I preferably produce the diminuendo and crescendo effects in printing the positive from the negative films. The succeeding series of views are preferably overlapped upon the positive film as in the old process but unlike the old process the intensity of the printing light is gradually diminished in rinting the latter ortion of the first series and the intensity of t e light is gradually ncreased in printing the overlapping portion of thesucceeding series, it being understood that the diminuendo and crescendo portions of the two series which 'a-re' overlapped are preferablysubstantially equal in length. In

projecting-the two series of images the positive film"-'is run through the projector continuously-and upon reachmg the end of the first series of views the first series gradually merges into the second series.

By my new method the camera operator, who has many details to occupy his attention and who is frequently required to operate under difiicult conditlons, is relieved of attending to the dissolving effect. In printing the positives from the negatives the provision for the dissolving phenomenon can be more carefully and accurately made; and, in the event that the first positives do not dis play the desired efl'ect, the rinting can be so varied as to provide the esired effect in subsequent positives. Moreover, should portions of the negative films be undesirable they may be eliminated without destroying the dissolving. efiect inasmuch as the .provision for the effect is first made in the posi tives.

However, I believe the most unique and desirable use of the present invention to be in the production of multiplex films, whether the complemental image be disposed side by side as in the additive processes or in. superposition as in the subtractive processes. The particular utility of the invention for color work is due in part to the particular stage of the process of exposing, printing and projecting, in producing motion pictures, in which I introduce the dissolving effect, and in part to the adaptability of my improved method of producing the described diminuendo and crescendo effects. In applying my invention to the subtractive process-of color cinematography the respective series of complemental positives may either independently at different times or they may be printed concomitantly as disclosed in m prior application Serial No. 149,7 91, filed February 28, 1917. Moreover, either white light, similarl colored light or, as in prior application 7 rial No. 112,378 above referred to, light of different colors may be employed to print the respective com plemental series. In applying the invention be printed to the additive process of color cinematography the respective series of positives may, be printed in any desired manner, as for ex;

r st to Daniel F. Comstock No. 1 390,983 granted In either event the ample in the manner disclosed in the September 20, 1921.

difliculties of the old dissolving method are overcome as will now be descrlbed q."

which have exceedingly sensitive emulsions and correspondingly short straight portions j in their, contrast gradients, the ordinary positive films are relatively very slow and have contrast gradients whose straight portions are long. The straight portions of the gradients for each of .the complemental series of positive images can be made coincident or at least parallel by suitably adjusting the light values in the printer and the degrees of development in developin the respective series of positives, or by sultably choosing ducing the diminuendo and crescendo por-' tions of the positive films, is avoided, the decrease of intensity not extending much if any below the straight portions of the contrast gradients. Thus, in introducing the dissolving efi'ect in the printing process in stead of in the exposing process the rela tive color values of the complemental images projected upon the screen are not unbalanced during the transition from one scene to another. The advantages resulting from my new method ofintroducing. the dissolving eflect, wherein the shutter opening is gradually varied in size, will be apparent from the detailed description of the mechanism for the purpose as hereinafter set forth.

Suitable a paratus for practicing the method therein claimed is shown in Patent No. 1,417,005 granted May 23, 1922 on my copending application Serial No. 176,652,

filed June 25, 1917, of which this is a continuation in part. I claim: 1. In the art of cinematography the meth- Unlike the panchromatic negative films, 3

0d of dissolving one scene into another scene, comprising gradually decreasing the intensity of the light in printing the last of the series of views of the first scene, gradually increasin the intensity of the light in printing the first of the series of views of the second series, and projecting the said first and last of the respective series of views in overlapped relationship so that the first series gradually merges into the second scene.

2. In the art of cinematography the method of producing a transparency having overlapping series of views, the overlapping portions of which gradually decrease in intensity in opposite directlons, comprising printing upon a sensitive strip one series of views, gradually decreasing the intensity of the light throughout the latter portion of the series, and printing upon the sensitive strip another series of views, gradually increasing the intensity of the light throughout the first position of the latter series, the two series being so printed upon the strip that the said latter portion and the said first portion of the respective series overlap.

3. In the art of cinematography the method of dissolving one scene into another scene, comprising gradually decreasing the shutter opening in printing the last of the series of views of the first scene, gradually increasing the shutter opening in printing the first of the series of views in the second scene, and projecting the said first and last of the respective series of views in overlapped relationship so that the first scene gradually merges into the second scene.

4. In the art of cinematography the meth- 0d of producing a transparency having overlapping series of views, the overlapping portions of which gradually decrease in intensity in opposite directions, comprising printing upon a sensitive strip one series of views, gradually decreasing the shutter opening throughout the latter portion ofthe series, and printing upon the sensitive strip another series of views, gradually increasing the shutter opening throughout the first portion of the latter series, the two series being so printed upon the strip that the said latter portion and the said first portion of the respective series'overlap.

5. In the art of color cinematography employing a plurality of series of images of the object field the respective series of which correspond to different dominant hues, the method of dissolving one scene into another scene, comprising gradually decreasing the intensity of the light in printing the last of the plurality of series of negatlves of the first scene, gradually increas-. ing the intensity of the light in printing the first of the plurality of series of negatives of the second scene, and projecting in overlapped relationship'the rtionsof the series of positives corresponding to the said first and last of the series of negatives, so that the first scene gradually merges into the second scene without undue variation in color values.

6. In the art of color cinemato aphy employing a plurality of intercala series of images of the object field, the respective series of which correspond to different dom- 76 inant hues, the method of producing a transparency having the series of images of one scene overlapping with the series of images of another scene, the overlapping portions of which gradually decrease in intensity in opposite directions, comprising printing upon a sensitive strip the plurality of intercalated series of images of the one scene, gradually decreasing the intensity of the light for each series throughout the latter B5 portion of the scene, and, in printing upon the sensitive strip the plurality of intercalated series of images of the other scene gradually increasing the intensity of the light for each series throughout the first portion of the scene, the two scenes being so printed that the said latter portion and the said first portion of therespective scenes overlap, whereby, in projecting, the first scene may be caused gradually to merge into the second scene without undue variation in color values.

7. A process of making a dissolve between two successive scenes of a moving picture film, which com rises printing from the last few photograp s of that portion of a moving picture film which corresponds to a given scene, such photographs being of approximately equal intensity, a succession of prints upon a moving picture film, such 1 succession of prints being of' successively lower intensity, such successively lower intensity being produced by gradually reducing the light admitted to such printing operation, also printing upon the said portion 110 of such second-mentioned film from the first few photographs of that portion of a moving picture film which corresponds to the commencement of the succeeding scene, such photographs also being of approximately equal intensity, a succession of prints of successively greater intensity, such successively greater intensity being produced by gradually increasing the light admitted to such printing operation, the margins of the two sets of prints being substantially coincident, and thereafter developing the said secondmentioned film.

8. A process of making a positive picture film having a dissolve between two suc- 125 cessive scenes, which comprises exposing the negative film as if no dlssolve effect were to be made, developing the negative, thereafter printing from the latter portion of that section of a resulting film of substantially standard intensity-which corresponds section of a resulting film of Substantially to a given scene of the finished picture, a succession of prints upon a given portlon of a film, such succession of prints being of gradually and successively decreasing intensity, such successively lower intensity being produced by gradually reducing the light admitted to such printing operation, also printing upon same portion. of last-mentioned film, from the first portlon of that the negative film for such two scenes, as if no fade effects were to be made, thereafter printing from-the later portion of that section of the negative film which corresponds to a given scene of the finished picture, a

succession of prints upon a given portion of a positive film, such succession of prints being of gradually and successively decreasing intensity, the first of such succession of prints being of approximately standard intensity, and thelast of such succession of prints being so faint as to be substantially negligible, also printing u on such portion of positive film, from the rst portion of that section of the negative film which corresponds to the next succeeding scene of the finished picture, a succession of prints, such last-mentioned succession of prints being of gradually and successively increasing intensity, starting with a print which is so light as to be substantially negligible and finishing with a print which is of substantially standard intensity, by varying the amount of light admitted to both of said printing operations, and thereafter developing the printed positive.

10. In the production of dissolve efiects in printing a moving picture film, the steps masses of'print'ing from the p'ortionj'of a developed film corresponding to the latter portion of that section of a film which corresponds to a given scene of the finished picture, a succession of prints upon a'given portion of a film, such succession of prints being of successively decreasing intensity, by successively decreasing the amount of light reaching the developed film during such printing operation, also printing upon same-portion of Such second-mentioned film, from the first eflect from one scene into another scene, by

reducing in a gradual way the light reaching the film durin the printing operation, by reducing the lig t a given fraction of the whole in each picture from full printing density of light to such an amount of light as will produce substantially no effect, and also fading in by increasing in a radual way the light reaching the film during the rintingoperation from such an amount of ight as will produce substantially no effect to substantially full printing intensity of light, thus dissolving one scene into the next.

12. A process of producing a fade, which comprises the step, in the printing operation, in which light passes through the successive frames of a developed moving picture film onto a sensitized film, of successively and graduallychanging the amount of light supplied to said developed film, between two limits, one of said limits representin such an amount of light as will produce su stantially standard intensity printing, and the other of said limits representing such an amount of light as will produce such a small amount of printing as to be negligible.

Signed by me at Boston, Massachusetts, this 14th day of Nov. 1921.

- WILLIAM BURTON WESCOTT. 

